Abstract: A method of digitally modelling a three dimensional shape comprises the steps of acquiring a plurality of images of the object including images in different orientations, identifying sections of the object, for each section masking the images so as to exclude other sections and deriving a digital representation of the shape of that section from the silhouette thereof, and joining the digital representations of the sections to form a digital representation of the three dimensional shape. It is naturally preferable for the sections to be line-convex, but it may be useful to compromise and select sections that are only nearly so. In this way, a number of 3D representations are prepared and stitched together to form a whole. The method can be implemented on a computer.